How to select antenna for CB?

Well, one of the more important mods to my truck is going to be a CB radio. I'm getting it mainly for trail use and emergencies. I hate Cell Phones so you can see why I am getting the CB.

I have already decided on the Cobra 75WXST because of its small size and reputation. Now I need to select an antenna. I don't know anything about antennas and am horrible with electronic stuff. I plan on mounting the antenna on my toolbox. I also don't want something thats extraordinarily tall. I only am looking for 2-3 miles range.

What should I get? If anybody wants to post pics of their set up, that works to.

 

I'm no expert, but I've done some research for CBs on two trucks recently.

If you don't mount the antenna on your roof, get a "no ground plane" antenna. This means that there is no flat metal surface beneath the antenna to help keep the transmission power horizontal.

The antenna will need to be tall enough that it sticks up above the cab or your forward transmission will suck. How high it needs to be depends on the antenna type.

I'm assuming your toolbox will be metal, and the antenna will be grounded to that. You'll also need to make sure the toolbox is grounded to the truck's chassis. Since the bed is plastic this is absolutely necessary. Depending on the hinges and how well the lid makes contact with the tool box you may even want to connect a ground wire between the lid and box.

Hope that helps a little.

 

You got a link to that mount?

I'm going to be buying a UWS Low profile box, all metal. How do I go about grounding the tool box? I know that probably is a noob question but I suck at electronic stuff and I admit it.

Wow. I'm not good at math at all, so I probably never would have been able to do that. Thats a huge help!

 

I have a Firestik II mounted to my rear bumper. I have a 2.5-3 mile max range.

 

Here is a picture of where it is mounted.

 

im running a 3' fiberglass antenna so as to clear the parking garages... got it mounted on my bedbar and i get a few miles on it...

im also running the 75WXST due to the compact size... great radio...

 

LOL, This one mad me laugh!

The best antenna that can reach the greatest distance for the low watts a stock CB radio will put out is a Willson 500 Magnet mount with a ground plaine kit... I would also consider the Cobra Classic LTD they are really good radios that are built tough and get a great signal range.

You might also wanna look in to getting a Linear Amplifier (10 Meter). On a clear summer morning you will be able to hit some 'Skip' and be able to talk over 1000 miles away...

 

"The best antenna that can reach the greatest distance for the low watts a stock CB radio will put out is a Willson 500 Magnet mount"
I am going to respectfully disagree magnet mount antennas suck.The best antenna is a nmo style mount (ground plane is better) as long as the surface its being mounted to is metal (conductive). Why does the equation the other member wrote make you laugh? He hit it right on the nose.

"You might also wanna look in to getting a Linear Amplifier (10 Meter). On a clear summer morning you will be able to hit some 'Skip' and be able to talk over 1000 miles away"
THIS IS ILLEGAL DO NOT DO IT
The only people who are allowed to use a linear amplifier are amateur radio operators (on the appropriate bands) . We are licensed from the FCC. You could possibly cause damage to yourself , others and your equipment.


FYI
here is an interesting article to read about CB a violator and the cost involved

The Commission ordered that, pursuant to Section 503(b) of the Act and Sections 0.111, 0.311 and 1.80(f)(4) of the Commission's Rules, "CB Shop and More is liable for a monetary forfeiture in the amount of $7,000 for willfully and repeatedly violating Section 302(b) of the Act, and Section 2.803(a)(1) of the Rules."

http://www.arrl.org/news/stories/2008/03/26/10025/?nc=1

 

very good!

here are some other helpful hints and rules when building/designing antennas. These were borrowed from a ARRL Technician class book


The basic rule is in antenna construction is "Longer the wire, the lower the resonance,shorter the wire the higher the resonance."


234 / Frequency in MHz = Length in Feet

A vertical antenna is a 1/4 wave antenna and is half the size of a dipole. It's highly common because of its space saving characteristic. It is found everywhere from the antenna on your FM Stereo system to your walkie-talkie





468 / Frequency in MHz = Length in Feet


A dipole is a 1/2 wavelength antenna. To create a dipole you must determine the following:
1st.) What frequency band
2nd.) What the wavelength is at that frequency.
3rd.) How long a 1/2 wavelength is in feet or meters at that frequency.

 

Because the equation is way over kill... 99% of people are not going to know what they are looking at.

As far as magnet mounts 'Sucking' thats your opinion, The wilson 5000 with a ground plain kit is a REALLY good antena IMO its able to handle alot of wattage and your RF Calibration is always perfect... Which means no power is being wasted or kicked back in to the finals of your transmitter, which will eventually burn it up it....

Amplifies are illegal on Citizens Ban radios, yes but what's not illegal with anything These days... As far as causing harm to your self? Give it a rest, a low frequency like 27mhz is not going to doing anything with power pumping through it. The danger starts when you start climbing to the high frequency range because the higher the freq is the the more directional it becomes and RF burn becomes a real factor... But not on 27mhz, LOL

Talking skip is fun and is not illegal.

 

1/4 wave length antenna is great for mobile CB use. A great antenna is the 102" whip. Problem is a 102" whip (8.5') antenna is a pain in the arse. Thus the other shorter CB antennas use a coil and a stinger to approximate a 102" whip.

Personally I use a Wilson 5000 mag mount on the center of my DC. I would prefer to run a thru the roof mount but I can't bring myself to punch a hole in a brand new truck. If it wasn't such a long run to the frame I'd run a ground wire from the antenna to the frame.

I run a Cobra SSB rig that has been peaked and tuned to put out a 4 watt dead key carrier on AM.

I've been messing with CBs since 1973, my 1st was a Cobra CAM 89, which I still have BTW.

 

Not meaning to change subjects too much, but how do the hand-held radios compare.

I know absoutley nothing about CB's.

 

My old specialty...wanna "really get out" your transmit? 102" stainless steel whip bumpermounted and a gutterclip on your roof. When you're out in the wide open unclip that sucker and let it ride straight up for max range of 5-10 miles!

 

IMO not very well unless you can attach an outside antenna. Most don't put out the max legal of 4 watts. For trail use they do ok.

 

I should add that it is imperitave to "match" your antenna to the transmitter otherwise prolonged mismatch can burn out the final coils in radio rendering it useless. Your radio dealer should show you how to do it...if you need I will explain it to you here

 

Absolutely you must match the antenna to the transmitter. This is known as SWR. 1:1 is perfect, anything below 1.5:1 is good.

 

I have no idea what that means. I fail at electronics.

Someone wanna just give me a link to what I need to pare with the Cobra 75WXST?

 

Any antenna you get will require a matchup. So you have a few good suggestions here, also you can shop your local Radio shack or look up a ham radio shop there. Once you get it I'll walk you through the process. Oh, and you'll need to either buy or borrow what is called an "SWR" meter. I read that you don't want to be bothered with details like this-I get ya but it's a neccessary evil with any transmitter!

 

well basically... It's all about how much you put into it. i chose a 105" (8') steel whip antenna. I love it because it picks up so much better than anything else. You hear guys talk about talking 2-3 miles away.... that aint shit. I can easily talk to people out of state and all across the state. But then again I run a linear amplifier on mine to which puts out a TON of power. Driving around places with TV's or stuff it will black them out because of the power it puts out. But basically, you can get a good antenna and work on your SWR or (Standing Wave Ratio) so basically you can hear/talk further than other people can. Grounding out the antenna will definitley lower your SWR and the lower it is the better. Good antenna's are steel whips, firestick, or Wilson such as Wilson 1000.